Before this commit, many files are using std::string without including
<string>. It can work accidentally but causes issues when refactoring,
especially if using operator <<() which is included implicitly by some
compilers.

To find guilty header files, I used:

    grep -l "^ *std::string" $(grep -L "#include <string>" $(find . -type f -name "*.h"))

which finds all files containing "std::string" at the beginning of a line
(usually a member or variable declaration), but not "#include <string>".
And then this script to add the includes (plus some manual ediing):

    #!/usr/bin/env python3

    import re
    import argparse

    def fix_file(filename, header):

        with open(filename, "r") as f:
            content = f.read()

        matches = list(re.finditer(r"(#include .*\n)\n", content))
        if len(matches) == 0:
            print("no include!")
            sys.exit(-1)

        pos = matches[-1].end(1)
        open(filename, "w").write(content[:pos] + "#include <{}>\n".format(header) + content[pos:])

    if __name__ == "__main__":
        parser = argparse.ArgumentParser()
        parser.add_argument('--header', type=str, required=True)
        parser.add_argument('files', type=str, nargs='+')
        args = parser.parse_args()

        for filename in args.files:
            fix_file(filename, args.header)

This reverts commit 73b61450.

find \( -name "*.hxx" -or -name "*.h" -or -name "*.cxx" \) -not -path "*ThirdParty*" -print0 | xargs -0 sed -sri "/#include <vcl_deprecated_header.h>/d"

find \( -name "*.hxx" -or -name "*.h" -or -name "*.cxx" \) -not -path "*ThirdParty*" -print0 | xargs -0 sed -sri "s/vcl_complex/std::complex/g"

find \( -name "*.hxx" -or -name "*.h" -or -name "*.cxx" \) -not -path "*ThirdParty*" -print0 | xargs -0 sed -sri "s/vcl_(algorithm|complex|cmath)\.h/\1/g"

find \( -name "*.hxx" -or -name "*.h" -or -name "*.cxx" \) -not -path "*ThirdParty*" -print0 | xargs -0 sed -sri "s/std::complex\.h/complex/g"

find \( -name "*.hxx" -or -name "*.h" -or -name "*.cxx" \) -not -path "*ThirdParty*" -print0 | xargs -0 sed -sri 's/#include "(algorithm|cmath|complex)"/#include <\1>/g'

find \( -name "*.hxx" -or -name "*.h" -or -name "*.cxx" \) -not -path "*ThirdParty*" -print0 | xargs -0 sed -sri "s/([^<])vcl_(adjacent_find|and|binary|binary_search|copy|copy_|count|count_if|equal|equal_range|fill|fill_n|find|find_end|find_first_of|find_if|for_each|generate|generate_n|generators_|heap|includes|inplace_merge|iter_swap|lexicographical_compare|lower_bound|make_heap|max|min|max_element|merge|merge_|min_element|mismatch|next_permutation|nth_element|partial_sort|partial_sort_copy|partition|stable_partition|partitions_|pop_heap|prev_permutation|push_heap|random_shuffle|remove|remove_copy|remove_copy_if|remove_if|replace|replace_copy|replace_copy_if|replace_if|reverse|reverse_copy|rotate|rotate_copy|search|search_n|set_difference|set_intersection|set_symmetric_difference|set_union|sort|sort_|sort_heap|stable_sort|swap|swap_|swap_ranges|transform|unique|unique_copy|upper_bound|bitset|abs|acos|asin|atan|atan2|ceil|cos|cosh|exp|fabs|floor|fmod|frexp|ldexp|log|log10|modf|pow|sin|sinh|sqrt|tan|tanh|complex|real|imag|arg|norm|conj|polar|jmp_buf|longjmp|sig_atomic_t|raise|signal|va_list|ptrdiff_t|size_t|FILE|fpos_t|fopen|fclose|feof|ferror|fflush|fgetc|fgetpos|fgets|fwrite|fread|fseek|ftell|perror|clearerr|rename|fputc|fputs|freopen|fsetpos|getc|getchar|gets|putc|putchar|puts|rewind|setbuf|setvbuf|tmpfile|tmpnam|ungetc|printf|sprintf|fprintf|vprintf|vsprintf|vfprintf)/\1std::\2/g"

find \( -name "*.hxx" -or -name "*.h" -or -name "*.cxx" \) -not -path "*ThirdParty*" -print0 | xargs -0 sed -sri "s/<<vcl_log/<<std::log/g"

This reverts commit 81bed5ae, reversing
changes made to f3749c05.

share/otb directory contains i18n and maybe other data files for OTB.

This allows to simply some code.
* avoid search and install of i18n files in package scripts
* use of OTB_INSTALL_DESCR cmake variable for storing qgis description
* install qgis description to share/otb/description in all cases:
 ** build directory, otb, superbuild, remote modules?
 ** generate of missing description file when loading qgis plugin. (This
 always goes to share/otb/description)
 ** packaging in debian, ubuntu and binary packages
* unversioned otb doc folder. share/doc/OTB-X.Y -> share/doc/otb. This is where all VERSION , LICENSE are kept.