Pre processor syntax error correction, and some simple code formatting

[Strings-RH]

There are a few syntax errors in include/version.hpp

#if defined(SOL_COMPILER_CLANG)
	#if defined(SOL_COMPILER_CLANG != 0)

which should be

#if defined(SOL_COMPILER_CLANG)
	#if (SOL_COMPILER_CLANG != 0)

Also, while reviewing the remainder of version.hpp, the use of parenthesis on the second condition when using this pattern is inconsistent, so I have normalized the formatting throughout the file.

#if defined(SOL_SAFE_GETTER)
	#if SOL_SAFE_GETTER != 0

becomes

#if defined(SOL_SAFE_GETTER)
	#if (SOL_SAFE_GETTER != 0)