Gadgets/Coliru: Add GCC-4.9 and C++14 support
Gadgets/Coliru: Use g++-4.9 -std=c++14 as the default
Gadgets/Coliru: Fetch default compiler and language from element class
Index: Add several keywords to the static search index
Index: Fix several typos in the C/C++ identifier indices
Index: Reduce the number of repetitive lines in autolinker index

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