Let ends_with accept a series of pattern to check

[Remi-Gau]

Will it be a more complexity/performance issue to make it also accept cellstr for pat?

Originally posted by @nbeliy in #172 (comment)

[nbeliy]

I found that in matlab the string operations are sometimes more effectively treated by regexp than by dedicated functions.
Probably because regexp is compiled.
It could be beneficial to create a set of low level BIDS string operations and compile them:

• getting modality (string before '/')
• getting extension (string after first '.')
• getting suffix (string between last '_' and first '.')
• splitting entities in pairs key - value

I tried to write some of them (just a trivial string scan) but the performance is on par with regexp